As a participating Institution in the Primary Breast Cancer Therapy Group, (NSABP) we are contributing data from patients entered into the various group protocols. From Protocol B04 it becomes increasingly acknowledged, that there is no proven difference in survival after various types of local treatment, prognosis depending mainly on the presence or absence of micrometastases at distance at the time of the initial treatment. Consequently, to further test this hypothesis, a trial of breast preservation (protocol 6) is underway within the NSABP to compare the value of segmental mastectomy with and without breast irradiation vs. total mastectomy. All patients undergo axillary dissection and those with histologically positive nodes receive adjuvant chemotherapy. This crucial protocol will tell us the clinical significance of multicentricity in breast cancer, the exact role of radiotherapy in the non-mutilating treatment of breast cancer. It can be considered as the most important surgical onocology protocol being carried out in the world. In addition, a sequential series of adjuvant chemotherapy protocols is underway. Protocol 5 evaluated L-Pam versus placebo in positive node patients, Protocol 7 evaluated L-Pam and 5 FU versus L-Pam alone. Protocol 8 compared L-Pam and 5 Fu versus L-Pam, 5 FU and methotrexate. Protocol 9 compared the two drug regimen versus L-Pam, 5 FU and tamoxifen, also obtained definitive information on estrogen receptor values in over 2,000 patients. The present application seeks funding: a) To permit continued patient accrual in ongoing protocols. b) To continue followup of patients entered into protocols which are terminated. c) Collect appropriate biological material and information relative to such protocols. The new protocols are Nos. 11-12 in positive nodes patients comparing L-Pam and 5 FU, versus L-Pam, 5 FU and adriamycin. Patients with ER+ and PR+ tumors receive tamoxifen in both groups. Protocol 13, in negative node patients, those with negative hormonal receptors will be treated with sequential methotrexate and 5 FU, versus a control arm. Protocol 14, for patients with ER and PR positive status will receive tamoxifen or placebo. The overall aim is evaluation of surgical and adjuvant therapies to enhance disease-free and overall survival, to minimize surgical and psychological morbidity in breast cancer treatment. An ancillary aim is to enhance the multidisciplinary capabilities of this institution in clinical trials.